Imported Upstream version 5.18.0.167

Former-commit-id: 289509151e0fee68a1b591a20c9f109c3c789d3a

external/llvm/test/Transforms/EarlyCSE/fence.ll

@@ -1,87 +0,0 @@
-; RUN: opt -S -early-cse < %s | FileCheck %s
-; RUN: opt < %s -S -basicaa -early-cse-memssa | FileCheck %s
-; NOTE: This file is testing the current implementation.  Some of
-; the transforms used as negative tests below would be legal, but 
-; only if reached through a chain of logic which EarlyCSE is incapable
-; of performing.  To say it differently, this file tests a conservative
-; version of the memory model.  If we want to extend EarlyCSE to be more
-; aggressive in the future, we may need to relax some of the negative tests.
-
-; We can value forward across the fence since we can (semantically) 
-; reorder the following load before the fence.
-define i32 @test(i32* %addr.i) {
-; CHECK-LABEL: @test
-; CHECK: store
-; CHECK: fence
-; CHECK-NOT: load
-; CHECK: ret
-  store i32 5, i32* %addr.i, align 4
-  fence release
-  %a = load i32, i32* %addr.i, align 4
-  ret i32 %a
-}
-
-; Same as above
-define i32 @test2(i32* noalias %addr.i, i32* noalias %otheraddr) {
-; CHECK-LABEL: @test2
-; CHECK: load
-; CHECK: fence
-; CHECK-NOT: load
-; CHECK: ret
-  %a = load i32, i32* %addr.i, align 4
-  fence release
-  %a2 = load i32, i32* %addr.i, align 4
-  %res = sub i32 %a, %a2
-  ret i32 %a
-}
-
-; We can not value forward across an acquire barrier since we might
-; be syncronizing with another thread storing to the same variable
-; followed by a release fence.  If this thread observed the release 
-; had happened, we must present a consistent view of memory at the
-; fence.  Note that it would be legal to reorder '%a' after the fence
-; and then remove '%a2'.  The current implementation doesn't know how
-; to do this, but if it learned, this test will need revised.
-define i32 @test3(i32* noalias %addr.i, i32* noalias %otheraddr) {
-; CHECK-LABEL: @test3
-; CHECK: load
-; CHECK: fence
-; CHECK: load
-; CHECK: sub
-; CHECK: ret
-  %a = load i32, i32* %addr.i, align 4
-  fence acquire
-  %a2 = load i32, i32* %addr.i, align 4
-  %res = sub i32 %a, %a2
-  ret i32 %res
-}
-
-; We can not dead store eliminate accross the fence.  We could in 
-; principal reorder the second store above the fence and then DSE either
-; store, but this is beyond the simple last-store DSE which EarlyCSE
-; implements.
-define void @test4(i32* %addr.i) {
-; CHECK-LABEL: @test4
-; CHECK: store
-; CHECK: fence
-; CHECK: store
-; CHECK: ret
-  store i32 5, i32* %addr.i, align 4
-  fence release
-  store i32 5, i32* %addr.i, align 4
-  ret void
-}
-
-; We *could* DSE across this fence, but don't.  No other thread can
-; observe the order of the acquire fence and the store.
-define void @test5(i32* %addr.i) {
-; CHECK-LABEL: @test5
-; CHECK: store
-; CHECK: fence
-; CHECK: store
-; CHECK: ret
-  store i32 5, i32* %addr.i, align 4
-  fence acquire
-  store i32 5, i32* %addr.i, align 4
-  ret void
-}